Printing sheet reusability determination device, erasing device, image forming device, and printing sheet reusability determination method

Abstract

A printing sheet reusability determination device includes a sheet carrying path that carries a second state sheet obtained by erasing an erasable image from a first state sheet on which the erasable image is printed, an imaging portion that images the second state sheet on the sheet carrying path, an illumination portion that illuminates the second state sheet on the sheet carrying path at a first irradiation angle when images remaining on the second state sheet are photographed, and at a second irradiation angle smaller than the first irradiation angle when a projected image generated by illuminating the second state sheet is photographed, an irradiation angle changing portion that changes the first irradiation angle and the second irradiation angle, and a reusability determination portion that determines whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion at the first irradiation angle and determines whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion at the second irradiation angle.

What is claimed is: 
     
       1. A printing sheet reusability determination device comprising:
 an image erasing unit that erases an erasable image which is printed on a sheet using an erasable color material; 
 a sheet carrying path that carries a first state sheet on which the erasable image is printed and a second state sheet passed through the image erasing unit; 
 an imaging portion that images the second state sheet on the sheet carrying path; 
 an illumination portion that illuminates the second state sheet on the sheet carrying path at a first irradiation angle when images remaining on the second state sheet are photographed, and at a second irradiation angle smaller than the first irradiation angle when a projected image generated by illuminating the second state sheet is photographed; 
 an irradiation angle changing portion that changes the first irradiation angle and the second irradiation angle; and 
 a reusability determination portion that determines whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion at the first irradiation angle and determines whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion at the second irradiation angle. 
 
     
     
       2. The device according to  claim 1 , wherein the illumination portion includes a first light source portion disposed with the first irradiation angle and a second light source portion disposed with the second irradiation angle. 
     
     
       3. The device according to  claim 1 , wherein the illumination portion changes direction of illumination light from a light source and changes an irradiation angle from the first irradiation angle to the second irradiation angle. 
     
     
       4. A printing sheet reusability determination device comprising:
 a sheet carrying path that carries a second state sheet obtained by erasing an erasable image from a first state sheet on which the erasable image is printed; 
 an imaging portion that images the second state sheet on the sheet carrying path; 
 an illumination portion that has a pair of light sources which is opposite to each other and which is symmetrically disposed with respect to an imaging light axis of the imaging portion and that illuminates the second state sheet on the sheet carrying path; 
 a lighting switching portion that changes a first turned-on state in which the pair of light sources is all turned on and a second turned-on state in which either of the pair of light sources is turned on; and 
 a reusability determination portion that determines whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion with illumination in the first turned-on state, and determines whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion with illumination in the second turned-on state. 
 
     
     
       5. An erasing device comprising:
 a sheet carrying path that carries a first state sheet on which an erasable image is printed; 
 a printing image erasing portion that erases the erasable image on the first state sheet which is carried on the sheet carrying path; 
 a reading portion that applies illumination light to a surface of a second state sheet obtained by erasing the erasable image from the first state sheet in the printing image erasing portion, in an irradiation state where a projected image is easy to generate and in an irradiation state where the projected image is difficult to generate, and that reads a surface of the second state sheet for each irradiation state using the imaging unit; and 
 a reusability determination portion that determines whether or not to reuse the second state sheet based on an imaging result from the imaging portion according to the irradiation states of the illumination light. 
 
     
     
       6. The device according to  claim 5 , wherein the printing image erasing portion and the reading portion are disposed on the sheet carrying path. 
     
     
       7. The device according to  claim 5 , further comprising a stacking portion that stacks the second state sheet for which reusability is determined. 
     
     
       8. The device according to  claim 7 , wherein the stacking portion sorts a reusable second state sheet and a non-reusable second state sheet and stacks the sorted second state sheet. 
     
     
       9. The device according to  claim 5 , wherein the reading unit is disposed at both sides of a sheet carrying surface of the sheet carrying path. 
     
     
       10. An image forming device which reads an original document sent from an automatic document feeder using a scanner portion, and can change an image forming mode in which an image is formed on a sheet based on information for an image read by the scanner portion and a reusability determination mode in which a second state sheet obtained by erasing an erasable image from a first state sheet on which the erasable image is printed is determined for reusability, comprising:
 a reusability determination portion that determines whether or not to reuse the second state sheet based on read information for the second state sheet which is read by the scanner portion when the reusability determination mode is selected. 
 
     
     
       11. The device according to  claim 10 , wherein the scanner portion applies illumination light to the second state sheet in an irradiation state where a projected image is easy to generate and in an irradiation state where the projected image is difficult to generate, and the reusability is determined according to the irradiation states. 
     
     
       12. The device according to  claim 10 , wherein the second state sheet is carried from the automatic document feeder to the scanner portion. 
     
     
       13. The device according to  claim 10 , further comprising a display portion that displays non-reusability if the reusability determination portion determines the second state sheet as being non-reusable,
 wherein the second state sheet determined as being non-reusable stops being carried in a place where the second state sheet is easily removed. 
 
     
     
       14. The device according to  claim 10 , further comprising a tray that discharges the second state sheet determined as being non-reusable by the reusability determination portion. 
     
     
       15. The device according to  claim 10 , further comprising a sheet reversing mechanism that can automatically reverse front and rear sides of the second state sheet. 
     
     
       16. A printing sheet reusability determination method comprising:
 carrying a second state sheet obtained by erasing an erasable image from a first state sheet on which the erasable image is printed on a sheet carrying path; 
 causing an imaging portion to image the second state sheet on the sheet carrying path; 
 causing separate illumination means to illuminate the second state sheet on the sheet carrying path at a first irradiation angle when images remaining on the second state sheet are photographed, and at a second irradiation angle smaller than the first irradiation angle when a projected image generated by illuminating the second state sheet is photographed; and 
 determining whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion at the first irradiation angle and determining whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion at the second irradiation angle. 
 
     
     
       17. The method according to  claim 16 , wherein the illumination portion includes a first light source portion disposed with the first irradiation angle and a second light source portion disposed with the second irradiation angle. 
     
     
       18. The method according to  claim 16 , wherein the illumination portion changes direction of illumination light from a light source and changes an irradiation angle from the first irradiation angle to the second irradiation angle. 
     
     
       19. A printing sheet reusability determination method comprising:
 carrying a second state sheet obtained by erasing an erasable image from a first state sheet on which the erasable image is printed on a sheet carrying path; 
 causing an imaging portion to image the second state sheet on the sheet carrying path; 
 disposing a pair of light sources which is opposite to each other so as to be symmetric to each other with respect to an imaging light axis of the imaging portion and illuminating the second state sheet on the sheet carrying path by changing a first turned-on state in which the pair of light sources is all turned on and a second turned-on state in which either of the pair of light sources is turned on; and 
 determining whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion with illumination in the first turned-on state, and determining whether or not to reuse the second state sheet based on imaging information obtained by the imaging of the imaging portion with illumination in the second turned-on state.